XADM: No Option to Upgrade from Exchange 2000 Server Standard Edition to Exchange 2000 Enterprise Server (312426)

IMPORTANT: This article contains information about modifying the registry. Before you modify the registry, make sure to back it up and make sure that you understand how to restore the registry if a problem occurs. For information about how to back up, restore, and edit the registry, click the following article number to view the article in the Microsoft Knowledge Base:

256986 Description of the Microsoft Windows Registry

SYMPTOMS

When you try to upgrade from Exchange 2000 Server Standard Edition to Exchange 2000 Enterprise Server, the component selection dialog box in Exchange 2000 Server Setup may not display the Reinstall option that allows you to upgrade. Instead, the dialog box displays only the None option.

CAUSE

This behavior can occur if you originally installed the Standard Edition from the Microsoft BackOffice Server 2000 installation CD-ROM. The BackOffice Server version is a later build than the retail version of Exchange 2000 Enterprise Server. Exchange 2000 Server Setup is designed to prevent your "upgrading" to software that is actually an earlier version.

WORKAROUND

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

To work around this behavior, follow these steps:

Quit Exchange 2000 Server Setup.
Start Registry Editor (Regedt32.exe).
Locate the NewestBuild value entry under the following key in the registry:
HKEY_LOCAL_MACHINE\Software\Microsoft\Exchange\Setup
On the Edit menu, click DWORD, and then change the value in the Data box:
- If the Decimal option is selected under Radix, change the existing value (4629) in the Data box to 4417.
- If the Hex option is selected under Radix, change the existing value (1215) in the Data box to 1141.
Click OK.
Quit Registry Editor.
Rerun Setup. The component selection dialog box should now list the Reinstall option.

MORE INFORMATION

Though you do not usually "upgrade" to an earlier version of software, in some cases (for example, if you reach the Standard Edition 16-gigabyte limit), an upgrade to Exchange 2000 Enterprise Server may be your only recourse. The modification under NewestBuild in the registry allows the Setup program for Exchange 2000 Enterprise Server to regard the currently installed BackOffice version of Exchange 2000 Server Standard Edition as a version that is at the same build level.

The following list identifies the build numbers for Exchange 2000 Server products and tells how the products are packaged.

Build    Software Product                        Packaging
----------------------------------------------------------------------------------------------------
4417.x   Exchange 2000 Server Standard Edition   Stand-alone retail product 
4417.x   Exchange 2000 Enterprise Server         Stand-alone retail product 
4629.x   Exchange 2000 Server Standard Edition   Included with BackOffice Server 2000 retail product
4629.x   Exchange 2000 Server Standard Edition   Included with BackOffice MSDN product